### R code from vignette source 'grid.Rnw'

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### code chunk number 1: grid.Rnw:33-34
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library(grid)


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### code chunk number 2: grid.Rnw:43-44
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library(lattice)


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### code chunk number 3: trellisdata (eval = FALSE)
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## x <- rnorm(100)
## y <- rnorm(100)
## g <- sample(1:8, 100, replace = TRUE)


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### code chunk number 4: trellispanelplot (eval = FALSE)
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## xyplot(y ~ x | g, panel = function(x, y) {
##     panel.xyplot(x, y);
##     grid.lines(unit(c(0, 1), "npc"), unit(0, "native"),
##                gp = gpar(col = "grey"))
## })


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### code chunk number 5: trellispanel
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x <- rnorm(100)
y <- rnorm(100)
g <- sample(1:8, 100, replace = TRUE)
xyplot(y ~ x | g, panel = function(x, y) {
    panel.xyplot(x, y);
    grid.lines(unit(c(0, 1), "npc"), unit(0, "native"),
               gp = gpar(col = "grey"))
})


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### code chunk number 6: trellisstripplot (eval = FALSE)
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## xyplot(y ~ x | g, strip = function(which.given, which.panel, ...) {
##     grid.rect()
##     grid.text(paste("Variable ", which.given, ": Level ",
##                     which.panel[which.given], sep = ""),
##               unit(1, "mm"), .5, just = "left")
## })


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### code chunk number 7: trellisstrip
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x <- rnorm(100)
y <- rnorm(100)
g <- sample(1:8, 100, replace = TRUE)
xyplot(y ~ x | g, strip = function(which.given, which.panel, ...) {
    grid.rect()
    grid.text(paste("Variable ", which.given, ": Level ",
                    which.panel[which.given], sep = ""),
              unit(1, "mm"), .5, just = "left")
})


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### code chunk number 8: trellisgridplot (eval = FALSE)
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## someText <- paste("A panel of text", "produced using", "raw grid code",
##                   "that could be used", "to describe",
##                   "the plot", "to the right.", sep = "\n")
## latticePlot <- xyplot(y ~ x | g, layout = c(2, 4))
## grid.rect(gp = gpar(lty = "dashed"))
## pushViewport(viewport(layout = grid.layout(1, 2,
##                       widths = unit.c(unit(1, "strwidth", someText) +
##                       unit(2, "cm"),
##                       unit(1, "null")))))
## pushViewport(viewport(layout.pos.col = 1))
## grid.rect(gp = gpar(fill = "light grey"))
## grid.text(someText,
##           x = unit(1, "cm"), y = unit(1, "npc") - unit(1, "inches"),
##           just = c("left", "top"))
## popViewport()
## pushViewport(viewport(layout.pos.col = 2))
## print(latticePlot, newpage = FALSE)
## popViewport(2)


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### code chunk number 9: trellisgrid
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x <- rnorm(100)
y <- rnorm(100)
g <- sample(1:8, 100, replace = TRUE)
someText <- paste("A panel of text", "produced using", "raw grid code",
                  "that could be used", "to describe",
                  "the plot", "to the right.", sep = "\n")
latticePlot <- xyplot(y ~ x | g, layout = c(2, 4))
grid.rect(gp = gpar(lty = "dashed"))
pushViewport(viewport(layout = grid.layout(1, 2,
                      widths = unit.c(unit(1, "strwidth", someText) +
                      unit(2, "cm"),
                      unit(1, "null")))))
pushViewport(viewport(layout.pos.col = 1))
grid.rect(gp = gpar(fill = "light grey"))
grid.text(someText,
          x = unit(1, "cm"), y = unit(1, "npc") - unit(1, "inches"),
          just = c("left", "top"))
popViewport()
pushViewport(viewport(layout.pos.col = 2))
print(latticePlot, newpage = FALSE)
popViewport(2)